封育对沙质草甸土壤理化性状的影响

对不同封育年限沙质草甸自然恢复过程中土壤理化性状进行了测定和分析。结果表明,封育对沙质草甸土壤理化性状的改善有明显的促进作用。随封育时间的延长,土壤颗粒组成发生明显变化,>0.25 mm的中粗沙成分明显减少,0.05~0.25 mm的细沙成分明显增加,而且表层粘粉粒含量也明显增加;各取样层次土壤有机碳和全氮含量在不同封育状况下形成显著差异,并随封育时间的延长而显著提高;随封育时间的延长,土壤容重逐渐减小,土壤硬度逐渐增大。相关分析表明,土壤有机碳含量、全氮含量与0.25~0.05 mm的细沙含量及<0.05mm的粘粉粒含量表现出显著的正相关关系,而与>0.25 mm的中粗沙含量呈显著的负相关关系。

Soil Physical and Chemical Characteristics of Sandy Meadow in Natural Restoration Process

The soil physical and chemical properties of sand meadow in natural restoring processes were studied.The results showed that enclosure promoted the improvement of soil physical and chemical properties.With the enclosure years increased,the soil particle composition changed significantly,the coarse particle size fractions(>0.25 mm) decreased,but the fine particle size fractions(0.05~0.25 mm) increased significantly,and the clay particle size fractions(<0.05 mm) also increased,especially in the top soil(0~10 cm).There were significant difference of organic carbon and total nitrogen content among different restoration status in each soil layer,the content of organic carbon and total nitrogen enhanced significantly in the restoring processes.With the enclosure years increased,the soil hardness increased accordingly,but the soil bulk density decreased.Correlation analysis revealed significant positive relationships between the soil carbon concentration,soil nitrogen concentration and soil fine particle size fractions(0.05~0.25 mm) and clay particle size fractions content,however,there was significant negative relationships between the soil carbon concentration,soil nitrogen concentration and soil coarse particle size fraction(0.25~2 mm) content.